May I ask if the parameters of the control valve need to be reset?
Thread Content
The control valve used for regulating flow rate originally had a linear characteristic with a flow coefficient of 0.32 T/H; it has now been changed to an equal percentage type with a flow coefficient of 0.8 T/H. Do the P, I, and D parameters need to be adjusted again?
The PID parameters need to be reset!
If the flow characteristic of the control valve changes – for example, from linear to equal percentage – in other words, if the ratio between the displacement of the control valve and the resulting flow rate changes, this will inevitably affect the PID control parameters. However, the extent of this impact, as well as the amount by which the PID parameters need to be adjusted, depends on the actual circumstances. It is certain, though, that this will have an effect on the PID parameters.
One is that your traffic curve has changed, and your traffic coefficient has also changed; either change requires adjusting the PID parameters.
It feels a bit different, but luckily it’s a flow regulator, so it seems to have little impact.
The PID parameters need to be adjusted again, but the process is complicated and requires some trial and error.